knee strike

a knee strike is a technique strongly used in the ancient art of Muay Thai, it is widely known for its effectiveness in their use of elbow and knee strikes in addition to the general combatative nature of fist and feet. Muay Thai also uses hardened shin to kick and sweep opponents, as I have heard that Muay Thai fighters conditions their shin in various ways - kicking banana trees hundreds or thousands of times, rolling glass bottles, kicking, breaking and smashing other things to harden and deaden the nerves of the shin.
A knee strike is not only used in Muay Thai

it is also used in other martial arts all around the world. When you look at it, all martial art are the same, they may differ in origins, creators, movements, techniques and et cetera, yet they share common similarities in their philosophies and serve a common purpose, to fight and self-defense.
A knee strike is effectively and widely used in chinese martial arts - (omei has written instructions for knee strikes).
Striking an opponent into the chest with the knees can cause dramatic damage, fracturing, collapsing the ribs, puncturing the lungs, even stopping the heart. According to the National Geographic Fight Science - a tested knee strike of a Muay Thai warrior has caused more damage and exerted more power when compared to other kicks (back kicks, flying kick, front push kick etc.)
A knee strike is just a knee strike, as simple as that, it does not belong to a particular style nor form, it does not need to be credited to a particular form of martial art and a creator of a system. All human beings can use whatever part of their body for self defense purposes. Although nowadays, martial arts are widely considered as sport and performance, it's essence still lies as a fighting form - ways of fighting and defending with one's body (or weapon).



picture courtesy of www.shaolin.org, Flickr & Fight science